How To Bypass Low Oil Sensor On The Generator: Is It Advisabe?

Nowadays, generators are equipped with a low oil sensor as a safety measure that gives us warnings. The oil sensors shut down the generator automatically when the oil level is low. As a result, it protects the engine from harm that can permanently damage the generator motor. However, if you want to bypass the low oil sensor on the generator, unplug the yellow wiring coming from the switch. 

As much as it’s not recommendable, sometimes you have to! When your generator doesn’t start, rule out the low oil sensor issues. Typically, when you have a new generator with enough oil and not starting, the reason might be the low oil sensor. There is a possibility that the oil sensor can be stuck to the crankcase bottom when using a new generator. This makes the oil sensor detect no oil forcing the generator to stop even though the fuel level is full. In such a case, temporarily disconnect the low oil sensor by locating the wire connected to the sensor and disconnecting it from the connector.  Follow the steps below to bypass the oil sensor with ease:

Bypass Low Oil Sensor On The Generator

3 Simple Steps To Bypass Low Oil Sensor On The Generator 

Sometimes people bypass the low oil sensor on the generator when it is stuck to the cranks’ bottom.  Especially when the generator is new, and it won’t start. The other reason might be that someone wants to leave the generator for a long time before using it again. They may need to burn off what is left in the tank before storing it. 

Note that this is only a temporary fix. Later on, it would be best if you reconnected the wire after bypassing the low oil sensor before you damage your generator completely. 

Follow these three simple steps to bypass the oil sensor:

Step 1: Look For A Yellow Wire On Your Machine

The first thing you need to do is look for a yellow wire on your machine. Numerous brands work with yellow color. It is often found on the crankcase near the oil fill cap for various machines underneath the panel. If your model is slightly different, go through your generator manuals and locate its position easily. Make sure the generator isn’t running before bypassing the low oil sensor since the moving parts can cause unnecessary injuries.  Remember to keep away cigarettes, flames, and sparks from the generator at all times.

Step 2: Pull Apart The Green Wire Connected To The Yellow One

When you see a green wire connector on the yellow wire, pull it apart to disconnect the wiring.  Depending on the brand, the connector’s color can vary from one another. It’s in the section where two wires connect guarded by a colored shield. We refer to a green shield made of plastic, and it looks like a socket.

Step 3: Allow The Generator To Run For 15-30 Minutes

Please put on your generator and let it run for about fifteen to thirty minutes. It will allow the sensor to become unstuck from the engine’s bottom, especially when it’s new. When you are done, reconnect the low oil sensor to avoid damaging your generator.  But allow your generator to cool down first to avoid burn injuries.

Suppose the generator doesn’t start after disconnecting the low oil sensor, then there might be an issue somewhere else. Go through your generator checklist issue and try to find out the issue.

How You Can Test The Low Oil Pressure Switch On A Generator

The gasoline generator engine has an oil sensor switch, which will not enable the engine to start when the oil drops to a certain level. Since it causes the internal pressure to drop, you need to test the low oil pressure switch on your generator when this happens. To test, follow these instructions step by steps:

1. Take your generator and place it on a hard but level surface. Then take off the oil dipstick near the bottom of the engine. Check the oil level, and if it’s low, add some more.

2. Look for a wire coming off the engine oil switch and disconnect it. The oil switch wire will come from the engine, next to the starter. Once you locate it, go after the wire up to its harness.

3. Switch on and set the ohmmeter to the lowest ohms settings. Put the positive lead into the connector on the ohmmeter engine oil switch. The ohmmeter’s negative side places it on the engine’s perfect ground. Make sure there is no continuity.

4. Lastly, drain all the engine oil out, then check if there is continuity once more. Ensure there are no more than two ohms of resistance in your generator. Suppose the readings say otherwise; replace the switch and check again.

What Causes Low Oil Pressure?

There are various causes of low oil pressure in your generator that include:

Not Using Enough Oil

A low oil issue on your generator also causes low oil pressure. Sometimes you are adding the correct amount of oil in your model though it’s not going straight to the engine. Maybe there is a leak, or it burned by worn-out piston rings.  The older your generator gets, the more oil it will use.

The easiest solution is to add more oil, but if it leaks, it will not solve anything. Place a cardboard piece under the unit to find out where there is a leak. Afterward, replace or repair that part before adding the oil again.

Engine Wear

Consider how old your generator is whenever you are dealing with oil issues. Check the dipstick’s oil level; suppose it fall between add and full lines, then the low pressure could be due to the worn-out engine bearings. Such is when your generator has many miles on it because excessive use reduces the flow restrictions that lower the oil pressure.  The solution here is to invest in a new generator.

Defective Oil Pressure Gauge

Whenever you are having oil issues, check the accuracy of your gauges. Check the oil levels when the oil pressure warning lights come on. If they are safe and there are no weird noises or high temperatures, it could be the sensor issues. Confirm if the oil sensor is giving strange reading by double-checking.  Suppose that is the cause; you need to replace the oil pressure sensor and check one last time.

Apparent Low Pressure

If you are using a diesel generator, the pressure gauge allows real-time reports that enable the user to see how the unit runs. A lower number shows the lubricant does more but uses less pressure. When the pressure is normal, there is no need to worry. Please note some lubricants have higher pressure than others.

Clogged Filter

A clogged filter can cause oil issues on a generator. Whenever it is blocked with contaminants, it forces the bypass valve not to work properly, leading to lubricant starvation. A clogged filter is due to overextended oil, water, or soot contamination. You will need to unclog the filter for the generator to function properly.

Pump Wear

When the oil level is between the low and full mark on the dipstick and the engine is running loudly, it could be the oil pump possibly. The oil pump fails to function to its standard if worn-out and old. Turn off your generator until you replace the pump. After fixing it, the generator will run a lot quieter as usual.

What Happens If I Put Too Much Oil In My Generator?

Overfilling your generator can lead to premature wear on the model engine or internal parts.  This causes permanent damage to the engine and eventually leading to your generator failure.  When this happens, the excess oil can be directed to the air cleaner case or air filter, making the engine choke out and stall.

If it’s a small amount, there will be minimal risk, and you don’t need to worry about it. Just remember, when there is an accidental overfill, the oil needs to go somewhere. Be it into the vents, air housing, or the cylinders, and that’s why complete care needs to be taken to avoid such scenarios that can damage your device.

Can I Drive With No Oil Pressure Sensor?

It’s not recommendable to drive with no oil pressure sensor. Driving with low oil pressure or less oil in the system can easily ruin your vehicle engine by breaking the motor completely. Whenever you see the oil light is on when the car is running, you need to stop as soon as possible; it doesn’t matter if you drive. Check out where the problem is; if the oil is low, add some more before driving again.

How Long Can You Run A Generator Continuously?

You can run your generator continuously for an average of 7.5-12 hours. Though the need to add oil, do maintenance and other various factors limit the time, a generator can run without a break. It would help if you considered these factors to run a generator for maximum time. Furthermore, such as a car engine case, the main thing that limits a generator’s runtime is its fuel capacity.

Always divide the generator’s fuel capacity by its consumption rate to get its maximum runtime. Usually, it is determined by the amount of power you consume, and that formula will give you a proper estimate. Note that generator runtimes are indicated in the product’s specs.


Bypassing a low sensor on the generator is a temporary thing since it’s one of the precaution measures that give you signs and warnings of low oil. Even though sometimes this isn’t the case, it will surely help you identify your model’s hidden problem. Solving such issues will be a plus to you because the money that is supposed to be used for repairs or another model’s purchase is saved. On top of that, you will have avoided wasting time and thus enjoying its full functionality. Remember to reconnect the oil sensor to its place or face the consequences at your own cost.

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